[syzbot] [bcachefs?] KMSAN: uninit-value in bch2_alloc_v4_validate

[syzbot <syzbot+5c0423c85f295891c7f7@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    6e4436539ae1 Merge tag 'hid-for-linus-2024081901' of git:/..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=17cc9387980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=62f882de896675a6
dashboard link: https://syzkaller.appspot.com/bug?extid=5c0423c85f295891c7f7
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1338058d980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=11d0f7f3980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/75208f1b057a/disk-6e443653.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/eeb34e49cb7e/vmlinux-6e443653.xz
kernel image: https://storage.googleapis.com/syzbot-assets/bd6b9e2947c8/bzImage-6e443653.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/80d0f45895f2/mount_2.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5c0423c85f295891c7f7@syzkaller.appspotmail.com

bcachefs (loop0): recovering from clean shutdown, journal seq 8
bcachefs (loop0): Doing compatible version upgrade from 1.7: mi_btree_bitmap to 1.11: disk_accounting_inum
  running recovery passes: check_allocations
=====================================================
BUG: KMSAN: uninit-value in alloc_data_type fs/bcachefs/alloc_background.h:135 [inline]
BUG: KMSAN: uninit-value in bch2_alloc_v4_validate+0x80a/0x1c10 fs/bcachefs/alloc_background.c:256
 alloc_data_type fs/bcachefs/alloc_background.h:135 [inline]
 bch2_alloc_v4_validate+0x80a/0x1c10 fs/bcachefs/alloc_background.c:256
 bch2_bkey_val_validate+0x2ac/0x470 fs/bcachefs/bkey_methods.c:143
 bch2_btree_node_read_done+0x5be1/0x7790 fs/bcachefs/btree_io.c:1219
 btree_node_read_work+0x973/0x1960 fs/bcachefs/btree_io.c:1323
 bch2_btree_node_read+0x2e6b/0x36e0
 __bch2_btree_root_read fs/bcachefs/btree_io.c:1749 [inline]
 bch2_btree_root_read+0xa81/0x13f0 fs/bcachefs/btree_io.c:1773
 read_btree_roots+0x51c/0x1250 fs/bcachefs/recovery.c:516
 bch2_fs_recovery+0x422c/0x5c60 fs/bcachefs/recovery.c:844
 bch2_fs_start+0x7b2/0xbd0 fs/bcachefs/super.c:1036
 bch2_fs_get_tree+0x13e8/0x22d0 fs/bcachefs/fs.c:1946
 vfs_get_tree+0xa7/0x570 fs/super.c:1800
 do_new_mount+0x71f/0x15e0 fs/namespace.c:3472
 path_mount+0x742/0x1f10 fs/namespace.c:3799
 do_mount fs/namespace.c:3812 [inline]
 __do_sys_mount fs/namespace.c:4020 [inline]
 __se_sys_mount+0x722/0x810 fs/namespace.c:3997
 __x64_sys_mount+0xe4/0x150 fs/namespace.c:3997
 x64_sys_call+0x255a/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 ___kmalloc_large_node+0x22c/0x370 mm/slub.c:4113
 __kmalloc_large_node_noprof+0x3f/0x1e0 mm/slub.c:4130
 __do_kmalloc_node mm/slub.c:4146 [inline]
 __kmalloc_node_noprof+0x9d6/0xf50 mm/slub.c:4164
 __kvmalloc_node_noprof+0xc0/0x2d0 mm/util.c:650
 btree_bounce_alloc fs/bcachefs/btree_io.c:124 [inline]
 bch2_btree_node_read_done+0x52a9/0x7790 fs/bcachefs/btree_io.c:1192
 btree_node_read_work+0x973/0x1960 fs/bcachefs/btree_io.c:1323
 bch2_btree_node_read+0x2e6b/0x36e0
 __bch2_btree_root_read fs/bcachefs/btree_io.c:1749 [inline]
 bch2_btree_root_read+0xa81/0x13f0 fs/bcachefs/btree_io.c:1773
 read_btree_roots+0x51c/0x1250 fs/bcachefs/recovery.c:516
 bch2_fs_recovery+0x422c/0x5c60 fs/bcachefs/recovery.c:844
 bch2_fs_start+0x7b2/0xbd0 fs/bcachefs/super.c:1036
 bch2_fs_get_tree+0x13e8/0x22d0 fs/bcachefs/fs.c:1946
 vfs_get_tree+0xa7/0x570 fs/super.c:1800
 do_new_mount+0x71f/0x15e0 fs/namespace.c:3472
 path_mount+0x742/0x1f10 fs/namespace.c:3799
 do_mount fs/namespace.c:3812 [inline]
 __do_sys_mount fs/namespace.c:4020 [inline]
 __se_sys_mount+0x722/0x810 fs/namespace.c:3997
 __x64_sys_mount+0xe4/0x150 fs/namespace.c:3997
 x64_sys_call+0x255a/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 UID: 0 PID: 5177 Comm: syz-executor142 Not tainted 6.11.0-rc4-syzkaller-00008-g6e4436539ae1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
=====================================================


---
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